020316 MUANZA GS talk

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New Phenomena Searches at TEVATRON Run I Outline Run I at the TEVATRON Search for SUGRA: dilepton channel at CDF electron channel at D0 Search for large ED: monojet channel at D0 diphoton channel at CDF Conclusions Steve Muanza, IPN Lyon On behalf of CDF and D0 collaborations

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Collider in Run I TEVATRON Proton-Antiproton Collisions

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Detectors in Run I Silicon Vertex Detector Large Magnetic TrackingVolume Non-Magnetic Central Muon Spectrometer (Forward Toroid)

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Detectors in Run I Good Calorimetry: hermeticity, resolution Iron Toroid Muon Spectrometer, Large Acceptance

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RPC Gravity Mediated SUSY Breaking (MSSM, mSUGRA) MSSM Particle Content: SUGRA Models Parameters: : universal gaugino mass : universal trilinear coupling : higgsino mass parameter : ratio of 2 Higgs doublets vev : universal scalar mass R Parity: Conservation: Sparticles pair production LSP stable signature MSSM Phenomenology:

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Gluino Pair Production Gluino and Stop Decays Final State Topology Main SM Backgrounds LO contributions: (stop NLSP) gluino: Majorana sparticle Top dilepton events Like-sign: (Opp-sign: ) Very low Fake lepton SM Top pair production Diboson production SUGRA in dileptons at CDF

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Analysis Selection Results Expected events: Observed events: Trigger: L3 inclusive electron or muon (isolation, pTandgt;13-15 GeV,…) Lepton ID: track matching (e), shower shape (e), track-calo. isol. (both), Remove: conversions (e), cosmics (mu), Z peak (both), radiative Z Etmiss: andgt;25 GeV (isolated) Jets: at least 2 central jets with SUGRA in dileptons at CDF

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Interpretation of Run I Result Limit on cross section: Mass limit: SUGRA in dileptons at CDF Preliminary

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mSUGRA in electrons at D0 Gluino Pair Production/Decay Final State Topology Motivation Signal sensitive to high and moderate m0 region: complement to (dilepton and jets)+ETmiss Main SM Backgrounds

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mSUGRA in electrons at D0 Selection: NN (9-18-1) Preselection

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mSUGRA in electrons at D0 mSUGRA Limit t tbar : 16.8  5.2 WW +  2 jets : 1.4  0.3 QCD Multijet: 19.1  4.7 W +  4 jets : 43.0  7.6 Expected Events: 80.3  10.4 Observed Events: 72 Results

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Large Extra Dimensions Phenomenology: SM particles (open strings): confined to (3+1)-D brane Graviton (closed strings): can propagate in the bulk (¨weakness of gravity¨) Equivalence: massive gravitons (KK) in 4-D and massless gravitons (4+n)-D Ref: Guidice, Rattazzi, Wells, NPB 544 (1999) Ref: Arkani-Hamed, Dimopoulos, Dvali, PLB 429 (1998) Ref: Antoniadis, PLB 246 (1990) Theoretical Foundation: Quantum gravity scale MD can be O(1 TeV), solution to hierarchy problem

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Large ED Searches at Colliders Production Mechanisms Eöt-Wash Experiment Test Newton’s Law downto Ref: Adelberger et al, PRL 86 (2001) ED Nbers and Radii

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LED in monojets at D0 Njets = 1 or 2 ET(j1) andgt;150 GeV, ET(j2) andlt; 50 GeV j1 central (good quality) ETmissandgt; 150 GeV Reject events with isol. muons, Reject cosmics WZ background = 30.2 ± 4.0 QCD background = 7.9 ± 7.1 Expected Events = 38.0 ±8.2 Observed Events = 38 Results Selection

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Conservative Limit (no K-factor) LED in monojets at D0 Limits n=4 MDandgt;698 (840) GeV D0 DELPHI n=6 MDandgt;632 (580) GeV D0 DELPHI

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LED in diphotons at CDF Isolated photons ET(g) andgt;22 GeV, |h(g1)|andlt;1.0 Selection Results Backgrounds g+jets QCD dijets Signal

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LED in diphotons at CDF Cross section of: Free parameter to fit: Limits Add cosq* to fit, 127pb-1 Ref: PRL 86 (2001) (This analysis)

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Conclusions New Analyses of Run I Data Better sensitivity: Improved Selection Techniques Use of Full Calorimeter Acceptance Resulting in: Improved Limits Complementary and Competitive wrt LEP II Next Moves Have Just Started in Run II: Slightly Higher Energy Higher Luminosity Upgraded Detectors Improved Trigger Designs … News Soon

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Large ED Searches Different theoretical notations Dimensionless parameter Sign: destructive or constructive interference

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mSUGRA search in dileptons at CDF Estimated limit: (same observed and expected events than Run I analysis, with 2 fb-1) Prospects for Run II LED search in monojets at D0 n=2: sensitive to MD=920 1400 GeV n=5: sensitive to MD=700 900 GeV (with 2 TeV and 300 pb-1)